Adjustable timer cam assembly spring biased by contacts for normal engagement with synchronous motor driven gear

ABSTRACT

A time switch having a rotor of unitary construction mounted at its ends in slots and having a meshed gear connection with drive means. Switch means providing a biasing force to said rotor for maintaining the meshed gear connection and said rotor being adapted for manual rotation relative to said drive means and against the biasing force causing its ends to move in said slots and said gears providing the drive connection to move out of mesh.

United States Patent 151 3,700,837 Schulze-Berge 1 Oct. 24, 197 2 {54]ADJUSTABLE TIMER CAM ASSEMBLY [56] References Cited sPRING BIASED BYCONTACTS EoR NORMAL ENGAGEMENT WITH UNTED STATES PATENTS SYNCHRONOUSMOTOR DRIVEN 3,260,807 7/ 1966 Rulseh et al. ..200/ 38 FE GEAR 3,500,0053/1970 Brown ..200/38 B lnventor: Karl J. Schulu-Berge, Manitowoc,

Wis.

Assignee: AMF Incorporated Filed: July 6, 1971 Appl. No.: 159,615

US. Cl. ..200/38 R, 200/1 A, ZOO/38 A, 200/38 BA Int. Cl. ..H0lh 43/10Field of Search ..200/38, 17 R, 18, 166 J, l A

Primary Examiner-J. R. Scott Attorney-George W. Price et a].

[57] ABSTRACT A time switch having a rotor of unitary constructionmounted at its ends in slots and having a meshed gear connection withdrive means. Switch means providing a biasing force to said rotor formaintaining the meshed gear connection and said rotor being adapted formanual rotation relative to said drive means and against the biasingforce causing its ends to move in said slots and said gears providingthe drive connection to move out of mesh.

8 Claims, 3 Drawing Figures PATENTEU 24 I97? 3. 700 83 T [NVENTOR KARLJ. .SCHULZEERGE AGENT ADJUSTABLE TIMER CAM ASSEMBLY SPRING BIASED BYCONTACTS FOR NORMAL ENGAGEMENT WITH SYNCHRONOUS MOTOR DRIVEN GEAR Thisinvention relates generally to electric circuit controls and morespecifically to a time switch therefor which has a fixed repetativecycle for timed opening and closing at least one pair of switchcontacts.

Time switches of this general type, as shown in US. Pat. No. 3,391,258granted to RR. Virnoche, .lr., and assigned to the same assignee as isthe present application, are particularly adapted for use asrefrigerator controls. It should be understood, however, there is nointent to limit the present invention to such a single envlronment.

The construction of this type of a time switch is relativelyuncomplicated. A switch operating cam is provided with a gear which isdriven by the output gear of a synchronous motor. In normal use, thetime switch will startto operate when its motor is energized, and willcontinue to repetatively operate in accordance with its time cycle.

However, such time switches must be capable of being manually set whichrequires rotatably repositioning the cam. Since the type of synchronousmotor used to drive the cam normally is provided with a high ratiostep-down gear train, the motor output gear cannot be manually rotatedand a one way clutch connection between the cam and its drive gear istherefore required. It has been found that this construction addssubstantially to the cost of material and labor.

Accordingly, an object of the present invention is to provide animproved construction for time switches of the type described.

Another object of the present invention is to reduce the number of partsand to improve the reliability of the foregoing time switches.

' The present invention contemplates a time switch having a motor drivenunitary rotor mounted at its ends in slots. The rotor has a switch meansactuating cam and a drive gear releasably retained in mesh with a motoroutput gear by a spring bias provided by the switch means.

The foregoing and other objects and advantages will appear more fullyhereinafter from a consideration of the detailed description whichfollows, taken together with the accompanying drawings wherein oneembodiment of the invention is illustrated by way of example. It is tobe expressly understood, however, that the drawings are for illustrationpurposes only, and are not to be construed as defining the limits of theinvention.

FIG. 1 is a elevational view of a time switch made in accordance withthe present invention, with most of the cover broken away to expose theinternal operating mechanism thereof;

FIG. 2 is a view similar to FIG. 1 with the terminal end of the timeswitch removed and the drive connection between the motor and rotordisengaged; and

FIG. 3 is an end elevational view of the time switch of FIG. 1 with aportion of the case broken away.

Referring now to the drawings, a time switch made in accordance with thepresent invention is provided with a case having a side wall 11 and acontinuous peripheral wall or flange l3 defining a switch chamber withan open side closed by a cover 15. A portion 14 of the peripheral flange13 at one end of the case 10 is of a slotted double wall configuration.The wall 11 and cover 15 are provided with axially aligned slots 12 and16, respectively, disposed toward the other end of the case 10 oppositefrom the double walled flange portion 14.

A synchronous motor 18 is mounted on the outside of the case 10 and hasan output shaft and gear arrangement 19 which extends into the switchchamber through an opening in the wall 1 1.

The time switch is provided with switch means 20 comprising three springcontact arms 21, 22-and 23 each having a terminal end portion whichextends through one of the slots of the double walled flange portion 14,and is supported thereby. A spacer 24 is provided at the other end ofthe switch means 20 to limit the minimum closure between the freecontact ends of the two outer arms 21 and 23. The common contact arm 22is disposed between and is longer at its free contact end than the arms21 and 23.

The rotor 30 of the time switch has three distinct portions, namely, asingle lobe cam 31 for actuating the switch means 20, a shaft 32 mountedat its ends in the slots 12 and 16, and a gear 33 which meshes with theoutput gear 19 to provide a rotor driving connection. While the cam 31and gear 33 may be made as separate parts and fixedly mounted on theshaft 32, the rotor 30 preferably may be molded as a single piece.

The mesh of gears 19 and 33 and the contact area between the cam 31 andthe spring contact blade 21 or blades 21 and 22 are substantiallydiametrically opposite to one another or on opposite sides of the axisof the rotor 30. All of the blades 21, 22 and 23 of the switch means 20are always deflected out of their normal planes and exert a biasingforce urging the gear 33 into mesh with gear 19 and the ends of theshaft 32 toward the upper ends of the slots 12 and 16, as shown in FIG.1.

Manual rotation of the rotor 30, in a clockwise direction as viewed inFIGS. 1 and 2, against a nonrotating or a slowly rotating motor outputgear 19 urges the ends of the shaft 32 toward the other or lower ends ofthe slots 12 and 16, against the bias of the spring means 20, causingthe gear 33 to move out of mesh with the gear 19, as shown in FIG. 2. Itshould be noted that the slots 12 and 16 must be sufficiently long so asnot to limit the movement of the ends of the shaft 32.

It is preferred to have both shaft ends 32 movable in slots as ishereinbefore described. However, where the distance between the wall 11and the cover 15 is sufficient to permit disengagement of the gears 19and 33 by cocking of the rotor 30, one of the slots 12 or 16 may bemerely a circular opening. Preferably in the present construction asshown in the drawings, the opening 12 in the wall 11 which is closer tothe gear 33 would be elongated to form a slot while the opening 16 inthe cover 15 would be circular.

Although but a single embodiment of the invention has been illustratedand described in detail, it is to be expressly understood that theinvention is not limited thereto. Various changes may also be made inthe design and arrangement of the parts without departing from thespirit and scope of the invention as the same will now be understood bythose skilled in the art.

I claim:

1. In a time switch, the combination comprising:

a pair of spaced wall portions each having an opening generallycorresponding to the opening of the other wall portion;

at least one of said openings being elongated to form a slot;

a rotor disposed between said wall portions and having a drive gear, acam, and shaft portions at its ends rotatably disposed in said openings;

drive means including an output gear in mesh with said drive gear forrotatably driving said rotor;

switch means engaging said cam on the side of said rotor opposite fromsaid output gear and being actuated by said cam as it rotates;

said switch means providing a biasing force on said rotor urging saiddrive gear into mesh with said output gear and said shaft portionstoward corresponding sides of said openings; and

said rotor being adapted to be manually rotated relative to said outputgear and against the bias of said switch means causing one of said shaftportions to move along the length of said slot and said drive gear tomove out of mesh with said output gear.

2. The time switch in accordance with claim 1, and

both of said openings being elongated to form slots thereby permittingboth of said shaft portions to move along the lengths of said slots whensaid drive gear moves out of mesh with said output gear.

3. The time switch in accordance with claim 1, and

said switch means comprising:

a plurality of spring contact arms each having a supported terminal endand a free contact end; and

the free contact end of at least one of said spring contact armsengaging said cam and said arm being deflected out of its normal planefor providing the biasing force to said rotor.

5. The time switch in accordance with claim 4, and

all of said spring contact arms being deflected out of their normalplanes for providing the biasing force to said rotor.

6. The time switch in accordance with claim 1, and

said rotor being of a unitary construction.

7. The time switch in accordance with claim 6, and

said switch means comprising:

a plurality of spring contact arms each having a supported terminal endand a free contact end; and

the free contact end of at least one of said spring contact armsengaging said cam and said arm being deflected out of its normal planefor providing the biasing force to said rotor.

8. The time switch in accordance with claim 7, and

all of said spring contact arms being deflected out of their normalplanes for providing the biasing force to said rotor.

1. In a time switch, the combination comprising: a pair of spaced wallportions each having an opening generally corresponding to the openingof the other wall portion; at least one of said openings being elongatedto form a slot; a rotor disposed between said wall portions and having adrive gear, a cam, and shaft portions at its ends rotatably disposed insaid openings; drive means including an output gear in mesh with saiddrive gear for rotatably driving said rotor; switch means engaging saidcam on the side of said rotor opposite from said output gear and beingactuated by said cam as it rotates; said switch means providing abiasing force on said rotor urging said drive gear into mesh with saidoutput gear and said shaft portions toward corresponding sides of saidopenings; and said rotor being adapted to be manually rotated relativeto said output gear and against the bias of said switch means causingone of said shaft portions to move along the length of said slot andsaid drive gear to move out of mesh with said output gear.
 2. The timeswitch in accordance with claim 1, and both of said openings beingelongated to form slots thereby permitting both of said shaft portionsto move along the lengths of said slots when said drive gear moves outof mesh with said output gear.
 3. The time switch in accordance withclaim 1, and said cam and drive gear being fixedly mounted on said shaftportion of said rotor.
 4. The time switch in accordance with claim 3,and said switch means comprising: a plurality of spring contact armseach having a supported terminal end and a free contact end; and thefree contact end of at least one of said spring contact arms engagingsaid cam and said arm being deflected out of its normal plane forproviding the biasing force to said rotor.
 5. The time switch inaccordance with claim 4, and all of said spring contact arms beingdeflected out of their normal planes for providing the biasing force tosaid rotor.
 6. The time switch in accordance with claim 1, and saidrotor being of a unitary construction.
 7. The time switch in accordancewith claim 6, and said switch means comprising: a plurality of springcontact arms each having a supported terminal end and a free contactend; and the free contact end of at least one of said spring contactarms engaging said cam and said arm being deflected out of its normalplane for providing the biasing force to said rotor.
 8. The time switchin accordance with claim 7, and all of said spring contact arms beingdeflected out of their normal planes for providing the biasing force tosaid rotor.